72126820 has 12 divisors (see below), whose sum is σ = 151466364. Its totient is φ = 28850720.

The previous prime is 72126787. The next prime is 72126823. The reversal of 72126820 is 2862127.

It can be written as a sum of positive squares in 2 ways, for example, as 18045504 + 54081316 = 4248^2 + 7354^2 .

It is not an unprimeable number, because it can be changed into a prime (72126823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1803151 + ... + 1803190.

It is an arithmetic number, because the mean of its divisors is an integer number (12622197).

Almost surely, 2^72126820 is an apocalyptic number.

It is an amenable number.

72126820 is an abundant number, since it is smaller than the sum of its proper divisors (79339544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72126820 is a wasteful number, since it uses less digits than its factorization.

72126820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3606350 (or 3606348 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 72126820 is about 8492.7510266109. The cubic root of 72126820 is about 416.2608771097.

Adding to 72126820 its reverse (2862127), we get a palindrome (74988947).

The spelling of 72126820 in words is "seventy-two million, one hundred twenty-six thousand, eight hundred twenty".